Which of the following is NOT necessary when performing welding, cutting, or heating tasks?

Using oxygen for ventilation is not a standard or necessary practice when performing welding, cutting, or heating tasks. Instead, proper ventilation typically refers to ensuring that the workspace is adequately ventilated with fresh air to dilute and remove harmful fumes, gases, and particulates generated during these processes. This can be achieved through mechanical ventilation systems or natural airflow methods, but not by using oxygen directly.

On the other hand, using proper ventilation helps protect workers by minimizing exposure to harmful airborne contaminants. Providing personal protective equipment is crucial for safeguarding against potential hazards such as burns, electrical shocks, and exposure to harmful radiation or toxic fumes. Having a fire extinguisher nearby is essential as well, given that welding and cutting processes can pose fire risks due to the high heat and sparks generated. All these safety measures are important, while using oxygen directly for ventilation does not align with standard safety protocols in these tasks.